The spinal column is a biomechanical structure composed primarily of ligaments, muscles, vertebrae, and intervertebral disks. The biomechanical functions of the spine are numerous. One such function is providing for support of the body, which involves the transfer of the weight and the bending movements of the head, trunk and arms to the pelvis and legs. Another such function is providing for complex physiological motion between these parts. Still another such function is providing for protection of the spinal cord and nerve roots.
Removal of an intervertebral disc is often desired if and when the disc degenerates. The surgical treatment of those degenerative conditions of the spine in which the spinal disks are in various states of collapse commonly involves spinal fusion, that is, the joining together of adjacent vertebrae through an area of shared bone. To this end, the disc is replaced with an intervertebral body fusion implant device that maintains proper spacing between and orientation of two adjacent vertebrae. When the shared bone extends across the area previously occupied by the intervertebral disk, the fusion is referred to as an “interbody fusion.” Fusion results in formation of a solid bony mass between adjacent vertebral bodies. The newly formed bony mass can assume a weight-bearing function and thereby relieve mechanical pain caused by an unstable degenerative disk. The bony fusion mass further can prevent long-term disk collapse or additional degenerative changes.
Interbody fusion of two adjacent vertebral bodies takes place over time. Accordingly, it is important for an intervertebral body fusion implant device positioned between two adjacent vertebral bodies to not only be accurately placed during initial placement, but to also maintain such position until interbody fusion is complete. Therefore, an intervertebral body fusion implant device is configured in a manner that allows for accurately placed during initial placement and for maintaining such position until fusion is complete is advantageous, desirable and useful.